High-pressure emergency-brake.



W. V. TURNER. HIGH PRESSURE EMERGENCY BRAKIL APPLIOATIo FILED 11110.27. 1907.

, 2 SHEETS-SHEET 1. Y

wnn Essis w. lv. TURNER. HIGH PRESSURE EMERGENCY BRAKE.

' APPLIOATIOI -FILED DEO* 27, 1907.

Patented Nov. 11, 1913.

2 SHEETS-SHEET 2.

mi) MN- WITN ESSES mf@ I M UNITED STATES PATENT oEEroE.

WALTER v. TURNER, or EDGEwooD, PENNSYLVANIA, AssIeNoE To THE WESTING- HOUSE AIE BRAKE COMPANY, 0F PITTSBURGH, TENNSYEVANIA, .A QQRPOBATlON 0F PENNSYLVANIA.

HIGH-PRESSURE EMERGENCY-BRAKE.

To all whom t may concern:

Beit known that I, VVALTE V. TURNER, a citizen of the United Stat s, residing at Edgewood, in the county of Allegheny and State of Pennsylvania, have invented new Emergency-Brakes, of which the following is a specification. l

My invention relates to automatic' fluid pressure brakes, and has for its principal object to provide an improved triple valve mechanism having/means for obtaining a high brake cylinder pressure in an emergency application of the brakes.

cilitate the release of the brakes after an emergency application,

It has been heretofore proposed to'provide a supplemental reservoir or other additional source of fluid pressure and a valve mechanism operating in an emergency application of the brakes for supplying air from the supplemental reservoir to the brake cylinder, With these prior devices, the supplemental reservoir pressure equalizes with the auxiliaryreservoir as well as the brake cylinder, so that in an emergency application, the filial auxiliary reservoir pressure 1s somewhat higher than the degree of pressure at which the auxiliary reservoir and brake cylinder alone would equalize, thereby requiring a' correspondingly higher train `pipe pressure to release the brakes, while the brake cylinder `pressure is much less than would be the case if the supplemental reservoir pressure were admitted to the brake cylinder only.

According to my improvements I provide means operating in an emergency application of the brakes for supplying air from the auxiliary reservoir to the brake cylinder while communication vfrom the supplemental reservoir to the brake cylinder is closed, and adapted upon equalization of auxiliary reservoir and brake cylinder pressures to close the auxiliary reservoir communication and open the communication for supplying air from the supplemental reservoir to the brake.

cylinder.

Another feature of my invention contemblow down or safety valve in an emergencyapplication of the brakes, whereby the auxil- Specification of Letters Patent. Appncation area December 27, 1907. serial' No. 408,258.

, source of.

Patented Nov. 11, 19,13,

4iary reservoir pressure is reduced after communication from the auxiliary reservoir to the brake cylinder has been closed, and the release of the brakes thereby still'further i; facilitated. and useful Improvements in High-Pressure Anot-her object of my invention is to pro- `vide an improved valvel mechanism for gov- Aerning the supply of air from an additional pressure to the brake cylinder,l which is adapted to be actuated by the emerf gency piston but having means independgent of said piston for maintaining the high pressure valve open throughout the emerfgency application.

Another object of my inventionis to a- In the accompanying drawings, :Figure l is a diagrammatic illustration of a car air brake equipment, with one form of my in- Evention applied thereto; Fig. 2 a vertical sectio-nal 'view-of a triple valve device em- :bodying a preferred form of my invention, showing the parts in full release position, 'the location of some 'of the ports being slightly distorted in o-rder to more clearly show the same; Fig. 3 a similar View, showiing the parts in the emergency application position, With-communication open from the auxiliary reservoir to the brake cylinder; Fig. 4 a similar view, with the parts in emergency position, but with the auxiliary reservoir cut ofi and communication open from the supplemental reservoir to the brake cyl- .inderg F ig. 5 a plan view of the main slide valve seat for the above triple valve device, showing the arrangement of ports therein; Fig.` 6 a face view of the main slide valve, showing the location of ports; and Figf a face view ofthe graduating slide valve,

adapted to be mounted on and to move relatively to said main slide valve.

According to Fig. l of the drawings, the

.car air brake equipment may comprise a train pipel, connected by a branch pipe 8 to a triple valve device 4, a brake cylinder v2,

` auxiliary reservoir 3 .and vsupplemental reservoir @connected respectively by pipes 5 and 7 to the triple valve device 4.

The triple valve device 4 comprises a casi ing having a piston chamber 10 containing the4 triple valve piston 11 and valve chamber 12, open v-tothe auxiliaryy reservoir and containingythe usual main slide valve 13 and auxiliary graduating valve .14.l An emergency valve mechanism is also embodied in the triple valve c aslng, and may comprlse an emergency piston 15, for actuating the usual quick action or train pipe ,vent valve 16, contained in the valve chamber 17, and controlling communication from the trainy pipe Apassage l18 to the chamber 20, below the emergency piston 15, which chamber is in lopen communication With the brake cylinder passage 21, the passage 18 being provided with a check valve 19, to prevent back flow of air from the brake cylinder to the train i e. p IAccording'to a preferred construction of my invention, the high pressure' emergency or supplemental valve mechanism is embodied in tlre triple valve casing and comprises a piston or movable abutment 23, operating in piston chamber 24, and a slide valve 25 actuated by said piston and con` tained in a valve chamber 26. The slide valve 25 controls communication from the supplemental reservoir 6, or other source of fluid pressure to the brake cylinder, the pipe 7, leading to said reservoir, being in open communication With the valve chamber 26. The valve seat for valve 25 is provided with a port 35, leading to the piston chamber of the piston and adapted to be controlled by the movement of said piston. A port 28 from the main slide valve seat also leads to the seatof the valve 25. In the normal inner position of the valve 25, a cavity 38 connects the ports 28 and 35, thereby7 establishing communication from the -main slide valve seat to the chamber 20 and the brake cylinder.

The supplementalreservoir 6 and valve chamber 26 may be charged from the train pipe through the main slide valve. chamber by providing a port 30, in open communication With the supplemental reservoir and leading to the main slide valve seat, the main valve 13 being provided With a through port 36, adapted to register with the port 30 in the release position of the triple valve. A feed groove 39 is provided around the piston 23 so 'that posite sides of the piston 23 are normally balanced, a spring 37 being provided for maintaining the piston 23 in its inner position when the pressures are thus balanced. The operation of the high emergency presy sure valve mechanism is preferably governed by movement of the emergency piston 15, and for this purpose, a valve 40 may 55 be provided, which is adapted to be actuated by the pistn 15 to open communication from the valve chamber 34 of said valve to chamber 17 The valve chamber 34 is connected by a passage 33 to the main slide valve seat, 60 and a passage 53 leads from the mainslide valve seat and opens to the valve seat of the slide valve 25. A cavity 41 in said valve 25 connects port 53 with port 32, leading to the piston chamber 24, in the normal po- 65|sition of the piston 23 and valve 25, and a the fluid pressures onv opcavity in the main slide valve is adapted to connect passages 33 and 53 in the emergency position thereof, thus establishing communication from the piston chamber 24 to the valve chamber 34, when the triple piston assumes theeniergency position.

The seat for the main'slide valve is provided with the usual brake cylinder exhaust port 27 which is connected to the brake cylinder in release position through a port 43 in themain valve 13, cavity 44 in the graduating valve 14, port 45, port 28, cavity 38 in the high pressure emergency valve 25, port 35, and emergencypiston chamber 20 to the brake cylinder passage 21 and the brake cylinder. The main slide valve is also provided with the usual service port 46, and the main valve seat with the emergency port 29, leading to the upper side of emergency piston 15. Fluid under pressure being admitted to the train pipe, flows through the usual feed groove around the triple valve piston to main slide valve chamber' 12 and the auxiliary reservoir. From valve chamber 12 air flows through the port 36 in the main Ivalve to port 30, and thence to the supplemental reservoir 6 and valve chalnber 26, and from valve chamber 26kthrough the feed groove 39 to piston chamber 24. Thus the above parts may be charged to the standard train pipe pressure, and the fluid pres- .sures being balanced on the opposite sides of the piston 23, the spring 37 maintains the high pressure valve mechanism at its inner position, in which the cavity 38 connects ports 28 and 35, so that the brake cylinder is open to the exhaust port 27, through the port 28, port 45, cavity 44 in the graduating valve, and port 43.

-A gradual reduction in train pipe pressure causes the triple valve piston 11 to move out to service position, in Which the service port 46 registers With port 28. Air is thus supplied from the auxiliary'reservoir to the brake cylinder, as ports 28 and 35 are connected by the cavity 38 in the high pressure emergency valve 25. When the 4flow of air from the auxiliary reservoir to the brake cylinder has reduced the auxiliary reservoir pressureto substantially that in the train pipe, the triple piston lshifts the graduating valve 14, closing the service port 46. The brake cylinder pressure may be increased as desired by vfurther reductions in train pipe pressure, and the brakes may be released .by increasing the train pipe pressure so 'that the main slide valve is shifted, uncovering the emergency port 29, as shown in Fig. 3. Fluid from the auxiliary reservoir then flows through the port 29 to the emergency piston 15, which is thereupon forced to its extreme outer position. In the present construction, a by pass 48 is provided around the emergency piston 15, so that air from the auxiliary reservoir flows to the chamber 20 and thence to brake cylinder passage 21 and the brake cylinder. The movement of the piston 15 also opens the train pipevent valve 16, so that Afluid from the train pipe flows past the check valve` 19, through the passage 18 to chamber 17 and thence to chamber 20 and the brake cylinder, producing the local venting of the train pipe and quick action in the Well understood manner. The valve 40 is also opened by theY movement of the piston 15 thereby opening communication from the piston chamber 24 through port 32, cavity 41 in valve 25, portl 53, cavity 55 in the mai-n slide valve 13, port 33, and Valve chamber 34 to chamber 17, and thence to chamber 20 and the brake cylinder. Fluid from' the louter face of piston 23 is thus vented to the brake cylinder, so that the higher supplemental reservoir pressure on the inner side of the piston 23 shifts the' piston and valve 25'outwardly.

In order to insure the full movement of and to maintain the piston 23 seatedon the` gasket 60, I preferably arrange the cavity 41v so as. to cut oil the port 53 during the outward movement of the valve 25 and connect the port- '32 with the atmosphere; for this purpose I provide an additional -port 31, which registers with cavity 41 during the final outwardmovement of the piston. The port 31 is connected by a cavity 5.6 in the emergency position of the main slide valve with an exhaust port 59, sot-hat the outer face of the piston 23 is open to the exhaust and is consequently firmly maintained in its outer position. In this position] the port 35 is open to the valve chamber 2G and the supplemental reservoir so that fluid therefrom flows into the port 35, but'. according to my.

locate the outlet of port 35 to the-chamber 20 so as to be'e'losed when the emergency piston4 15 moves outwardly t6 open the auxiliary reservoir by-pass 48.

Upon substantial equalization of auxiliary reservoir pressure into the brake cylinder, iston l5 is returned. .to its normal seat by t e valve spring 65, as shown in Fig. 4, thereby closing communication to the auxiliary reservoir and4 uncovering the port 35, fluid thereupon fiows from the supplemental reservoir through the port 35 to chamber 20 'obtained While the auxiliary reservoir pressure remains at the lower degree of pressure at which the same equalized into the brake cylinder, by reason 'of which the rel-ease of the brakes is facilitated.- v

In orderY to release 'the brakes after an emergency application, the train pipe pressure lis increased as usual and the triple valvepiston is therebyl shifted to release position. In this position a through port 61 in the main slide valve registers with port 31,' so that fluid 'from the auxiliary reservoir is admitted to the piston chamber 24 through port 31, cavity 41 in the valve 25 and port 32. Rort`36 also registers with port 30, so that the higher pressure in the supplemental reservoir and the brake cylinder causes a re. turn floiiv of fluid therefrom to the auxiliary reservoir. The opposing pressures on the piston 23 thus rapidly equalize vand' permit i the spring 37 to'return the piston 23`and a'valve 25 to the normal inner position, in 95 which the cavity 38 connects the ports 28 and 35, and the fluid in the brake cylinder is released through port 35, cavity 38 port 28, port 45, cavity 44 1n the graduatmg" valve 14, and port 43 to exhaust port 27.

Y 1.00 With the present construction, if 1t 1s desired to limit the brake cylinder pressure in service applications, a safety valve .51 is connected to port 52 leading to the passage 28, as this passage is open to the brake cylinder inservice applications, and the full' pressure -is retained -in emergency ap lications sm'ce passage 28 is then cut off om the brake cylinder. 'With this construction, when the parts are returned to release position, after .1 0 an emergency application, the-safety Yalve 51 being open to the port 28, an additional exhaust is provided, which assists in rapidly reducing the high pressure'in the brake cylinder. The necessity for additional ports 1n 115 the main valve for a safety valve is thus obviated.

Another feature of my invention consists in providing a through port 62 inthe main slide valve, which is adapted to register with a port extension v63 of the port` 28 1n the emergency position, so that after the pressure has equalized from the auxillary reservoir into the brake cylinder and the communication is closed, the auxiliary reservoir pressure is thcnreduced slowly through the restricted port 62, to the degree at which the safety valve 51 is adjusted, and the release of the brakes is thus still further facilitated, by reason of the low degree of auxiliary res- '130 ervoir pressure remaining on the inner face of the triple valve piston.` Further, by providing the above safety valve port 62, should the emergency piston 15 leak for any reason, so that the fluidl from the brake cylinder at high pressure fiows past the piston to the auxiliary reservoir, the pressure in the" auxiliary reservoir will be prevented from exceedin the degree for which the safety valve 1s adjusted.

It has heretofore been proposed to provide means in addition to the -usual feed groove around the triple valve piston, whereby the auxiliary reservoir is quickly recharged onreleasing the brakes after an application thereof, as by providing a through port in the main slide valve, which is adapted to register in release positionwith v a passage leading to the train pipe vent port for supplying air from the auxiliary reser# 18. With my present invention I may ut-ilize the port 33 for assisting in the quick recharge of the auxiliary reservoir and connected chambers, by providing a port 54 in the main slidevalve which opens into the main slide valve chamber, as by connecting the same to the port 36, and which registers with port 33 in release position.

4It will now be apparent that when Athe train pipe pressure is increased and the triple valve piston is shifted to release position, after an emergency applicatiomfluid from the train pipe lows past the check valve 19 into passage 18 to chamber 17 and unseats the valve 40, so that air flows to the passage 33 and thence through the ports 54 and 36 to the main slide valve chamber, the auxiliary reservoir and the supplemental reservoir.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is 1. In a fiuid pressure brake, the combina-v tion witha train pipe,'auxiliary reservoir, additional source of fluid pressure, brake cylinder, and a valve device operating upon a sudden reduction in train pipe pressure voir to the brake cylinder, of means operating upon equalization of auxiliary reservoir and brake cylinder pressures for opening communication from said additional source of fluid pressure to the brake cylinder.

2. `In a fluid pressure brake, the combination with a train pipe, auxiliary reservoir, additional source of fluid pressure, brake cylinder, and a valve device for supplying air from the auxiliary reservoir to the brake cylinder in an emergency application of the brakes, of means operating upon equalization of auxiliary reservoir pressure into the brake cylinder for opening communication from said additional source of fluid pressure to the brake cylinder.

3. I n a fluid pressure brake, the combination with a train pipe, brake cylinder', and

supplemental reservoir, of means for controlling a supply port from the supplemental reservoir to the bra-ke cylinder and an emergency piston for governing the outlet from said supplement-al reservoir supply port to the brake cylinder.

4. In a fluid pressure brake, the combination with a train pipe, brake cylinder, and supplemental reservoir, of means for controlling the admission of air from the supplemental reservoir to a passage for supplying air to the brake cylinder and an emergency `piston operating upon a sudden reductionin train pipe pressure for governing communication from said passage to the brake cylinder.

5. In a Huid pressure brake, the combination with a train pipe, auxiliary reservoir, brake cylinder, supplemental reservoir, and a valve device for governing the supply of air from the auxiliary reservoir to the brake cylinder, of means for controlling communication from the supplemental reservoir to a brake cylinder supply port and an emergency piston operating upon equalization of auxiliary reservoir and brake cylinder pressures for opening the outlet from said supply port to the brake cylinder.

6. In a fluid pressure brake, the combination with a train pipe, auxiliary reservoir, brake cylinder, supplemental reservoir, and a valve device for governing the supply of air from the auxiliary reservoir to the brake cylinder, of means for controlling communication from the supplemental reservoir to a brake cylinder supply port and an emergency piston operating upon equalization of auxiliary reservoir and brake cylinder pressures in an emergency application of the brakes for opening the outlet from said supply port to the brake cylinder.

7. In a fluid pressurebrake, the combination with a train pipe, auxiliary reservoir, brake cylinder, supplemental reservoir, and triple valve, of an emergency` valve mechanism operated by said triple valve upon a sudden reduction in train pipe pressure for supplying air from the auxiliary reservoir to the brake cylinder, and means governed by said emergency valve mechanism for opening communication from a supplemental reservoir supply port to the brake cylinder upon substantial equalization of the auxiliary reservoir pressure into the brake cylinder.

8. In a fluid pressure brake, the combination with a train pipe, auxiliary reservoir, brake cylinder, a triple valve device having a passage through which air is supplied from the auxiliary reservoir to the brake cylinder in service applications, and an additional source of fluid pressure, of means operated upon a sudden reduction in train pipe pressure for supplying airthrough said passage lfrom the additional source of pressure to aa n ` closing a supply port from the additional imams the brake cylinder, and a separate passage through Which air is supplied to the brake cylinder from the auxiliary reservoir.

9. In a fluid pressure brake, the combina` tion with a train pipe, auxiliary reservoir,A

brake cylinder, and an additional source of fluid pressure, of a piston operated in an emergency application of the brakes for controlling the supply of air first from the auxiliary reservoir and then from said additional source of fluid pressure to the brake cylinder.

10. In a fluid pressure brake, the combination with a train pipe, auxiliary reservoir, brake cylinder, and an additional source of fluid pressure, of a piston operated upon a sudden-reduction in train pipe pressure for supplying air from the auxiliary reservoir to the brake cylinder, and adapted upon equalization of the -auxiliary reservoir and brake cylinder Apressures to open communication l trom the additional source of Huid pressure to the brake cylinder. y

11. In a fluid pressure brakethe combination with a train pipe, auxiliary reservoir,

brake cylinder, and an additional source ofl -fluid pressure, of an emergency piston operated upon a sudden reduction in train pipe pressure for supplying air fr oin theauxiliary reservoir to the brake cylinder and for source of pressure to the brake cylinder and adapted upon substantial equalization. of the auxiliary reservoir ressure into the brake cylinder to open sai supply port. 12.`In a flilid pressure brake, the combination with a train pipe, auxiliary reservoir,

brake cylinder, andan additional source of fluid pressure,y of an emergency. piston operatedupon a sudden'reduction in train pipe pressure for supplying air from the auxiliary reservoir to the brake cylinder and for closinga supply port from the additional source of pressure to the brake cylinder and adapted upon substantial equalization of theauxiliary reservoir pressure inta the brake cylinder to close communication from the auxiliary reservoir to the brake cylinder and open said supply port to admit air from said additional source of fluid pressure tothe brake cylinder. Y

13. In a fluid pressure brake, the combination with a train pipe, auxiliary reservoir, brake cylinder, and supplemental reservoir, of an emergency piston, a triplevalve device operated upon a sudden reduction in train pipe pressure for supplying air from the auxiliary reservoir to and thereby operate said piston, and means overned by said piston for opening communication from the auxiliary reservoir to the brake cylinder and for closing a supply port from the sup-- plemental reservoir, and adapted upon equalization of the auxiliaryreservoir pres-` sure into the brake cylinder to closel the .trolling a supply port from the supplemental reservo-ir tothe brake cylinder, subject on one side to supplemental reservoir pressure'fand having an equalizing `p0rt for normally balancing the fluid pressures on opposite sides of said valve device, and an emergency piston operating in an emergency application for releasingA air from one side of said valve device to actuate the same.

15. In a fluid pressure brake, the combination With a train pipe, auxiliary reservoir, brake cylinder, supplemental reservoir and triple valve, of a piston and a valve actuated thereby for controlling a supply port from the supplemental reservoir to the brake cylinder, an emergency pistonand a vent valve operated thereby Vit'or releasing fluid from o-ne side of said supply piston through a port leading through the vtriple valve slide valve and said supply Valve, and means operating during the movement ofV said supply valve for closing said vent port' and opening a second port from said supply piston to the atmosphere.

16. In a fluid pressure brake2 the combination with a train pipe, auxiliary reservoir, brake cylinder, supplemental reservoir and triple valve, of a piston subject on one side to supplemental reservoir pressure and having an equalizing port, a valve actuated thereby for controllingja supply port from the supplemental reservoir to the brake cylinder, an emergency piston o erated by the triple valve upon a sudden re ucti'on in train pipe pressure, a vent valve actuated thereby for releasing air from one side of said supply piston throughla port leading through `the triple valve slide valve andl saidsupply valve, and means operating during the movement of the supply valveffor closing said vent port, and openinfr a second vent port from said supply pisiim, leading through the triple valve slide 4valve to an exhaust port.

17. 'Ina fluid pressure brake, the combination with a train pi e, auxiliary reservoir, brake cylinder an triple valve, of an emergency piston having-means for closing communication between said auxiliary reservoir and brake cylinder upon equalization of pressures and a blow down valve for limiting the degree of pressure in the auxiliary reservoir in an emergency application.

18. In a fluid pressure brake, the combination with a train pipe, auxiliary reservoir,'brake cylinder, and triple valve, of an emergency piston operated by said triple valve in 'emergency applications for supplying air from the auxiliary reservoir tothe brake cylinder, and adapted upon equalization of auxiliary reservoir and brake c linder pressures to close communication rom auxiliary reservoir to brake cylinder, and a blown down valve communicating with the auxiliary reservoir in emergency position, for limiting the degree of pressure in the auxiliary reservoir.

'19. In `a fluid pressure brake, the combination with a train pipe and brake cylinder,

A of an emergency piston forl controlling the der in service applications, said port being controlled by the emergency piston for also supplying iiuid to the brake cylinder in 'emergency' applications of the brakes.

21. In a fluid pressure brake, the combi-- nation with a train ipe, auxiliary reservoir, and supplemental) reservoir, of a valve for controlling the supply ofair from the supplemental reservoir to the brake cylinder, an emergency piston and a triple valve device for actuating said piston in an emergency application of the brakes, said triple valve device havingits brake cylinder port governed by said supply valve and said A emergency piston.

22. In a fluid pressure brake,the combination with a train pi e, auxiliary reservoir, brake cylinder, and sup lemental reservoir, of a valve mechanism or controlling a supply port from'the supplemental reservoir to the brake cylinder, an emergency .piston for effecting the operation of said valve mechanism, and means independent of' the emergency piston for maintaining said valve mechanism in open position.

23. In a fluid pressure brake, the com-bination with a train pipe, auxllia reservoir, brake cylinder, supplementa reservoir, and triple valve, of a valve` device for controlling the supply of air from said supplemental reservoir to the brake cylinder, 'an emergency piston and a valve operated v thereby in an emergency application for actuating said valve devlce, said valve being adapted to control communica-tion from the vtram pipe to a port open at the auxiliary reservoir in release position..

24. In a Huid pressure brake, the combination with a brake cylinder, a train pipe,

and two sources of fiuid under pressure, of a valve device for controlling commumcation from said sources to the brake cylinder and adapted to first supply Huid from one source and then from the other source of fluid pressure to the brake cylinder, and a piston and valve Voperated thereby upon a sudden reduction in train pipe pressure for controlling the operation of sa1d valve devlce.

,25. In a fluid pressure brake, the combination with a train pipe, a brake cylinder, and a' plurality of receptacles for fluid under pressure, of a valve device for controlling communication from said receptacles to the brake cylinder and adapted to first supply fluid from one receptacle and then from another receptacle to the. brake cylinder, and a piston and valve operated thereby upon a sudden reduction in train pipe pressure for controlling the operation of said valve device.

26. In a fluid pressure brake, the combination 4with a train pipe, a chamber the ressure in which operates to a ply the rakes, and two receptacles adapted to contain a supply of Huid under pressure, of a valve device operated by the iow of air from one receptacle to said chamber for closing communication from the other receptacle and means adapted to shift said valve device to close communication from the first rece tacle and to open communication from t e second receptacle to said chamber.

27. In a fluid pressure brake, the combination with .a train pipe, a chamber the pressurel in which operates to apply the brakes, and two receptacles adapted .to contain a supply of uld under pressure, of a valve device operated by the fiow of air from one receptacle for opening communication from said receptacle to said chamber and means for, shifting said valve device toclose Comunication from said receptacle and open communication from the other receptacle upon. equalization. of the pressure in the chamber and the first mentioned receptacle.

28. In a fluid pressure brake, the combination with a tram pipe and a chamber the pressure in which operates to effect an application of the brakes and a plurality of receptacles adapted to contain fiuid under pressure, of a valve mechanism adapted upon a reduction in train pipe pressure to admit fluid under pressure from said receptacles to said chamber and operating first to open communication from one rece tacle to said chamber and then close sa1d communication from said receptacle and open communication from another receptaclc, to said chamber.

29. In a fluid ressure brake, the combination with a bra e cylinder and train pipe,

of a triple valve device having a passage through which air is supplied from the aux iliary reservoir to the brake cylinder in service Vapplications of the brakes, a safety valve in said passage for limiting the pressure of fluid supplied to the brake cylinder, and means operating upon a sudden reduction in train pipe pressure for cuttingy off said passage and supplying fluid from the auxiliary reservoir through another passage to the brake cylinder.

30. In a iuid ressure brake, the combination with a bra e cylinderand train pipe, of. a triple valve device provided with a passage through which air is supplied from the auxiliary reservoir to the brake cylinder in service afplications, a safety valve in said passage or limiting the pressure in the brake cylinder, and means operating upon a sudden reduction in train pipe pressure for cutting off said passage from the brake cylinder.

In testimony whereof I have hereunto set my hand.

WALTER: V. TURNER. e Witnesses R. F. EMERY, WiL M. CADY. 

